A known method for producing ozone includes the steps of passing oxygen at 1 atmosphere and 25° C. through concentric metallised glass tubes to which low-frequency power at 50–500 Hz and 10–20 kV is applied. Due to the relatively slow change in potential (5 kV per millisecond), a corona or silent electric discharge is maintained between the electrodes. A disadvantage of this method is that energy is lost in the form of heat, and a relatively low yield ratio of ozone is achieved.